Distinguish missing CDP inventories from observed empty arrays, retain valid accessibility and worker siblings, and admit required fields before scope inference. Stop interpreting DOM documents without a usable string table. Validated producer semantics and simulated CDP provider boundaries; this does not establish real Chrome or Electron engine behavior. Refs #3376, #3379, #3850. Co-authored-by: 李云周 <154221037+YunzhouLi-hub@users.noreply.github.com> Co-authored-by: Kaoru0822 <208281322+kaoru0822-kitauji@users.noreply.github.com>